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1.
This paper examines the effects of disclosing greenhouse gas (GHG) information mandatorily on the cost of equity capital (COC) using a longitudinal unbalanced panel database of the United Kingdom's FTSE 350 firms for the period 2011–2016. We use a nonlinear panel quantile regression (PQR) model to examine the relationship between GHG disclosure (GHGD) and COC in the United Kingdom. This technique was supplemented by conducting a two-step generalised method of moment (GMM) estimation to address any concerns related to the potential existence of endogeneity problems. Our findings suggest that high-level GHGD appeared to be negatively associated with COC up to a certain level, which is known as the turning point; then, any increase in GHGD is likely to increase the COC. This means that the nonlinear association between GHGD and COC is evidenced in our study and takes a U shape. Likewise, our findings are associative of a moderating effect of the 2013 carbon disclosure regulation (CDR) on the GHGD–COC nexus. We argue that mandatory GHGD and GHG risk are linked so that those companies that are associated with higher GHG risk have a tendency to be better disclosers. Consequently, we urge regulators to design GHGD regulations in a way that mirrors corporate environmental risk and leads to a lower COC in order to align the interests of corporations with those of the society at large.  相似文献   
2.
人口老龄化是经济增长的一大阻碍,它对碳排放的影响是做出环境政策抉择的关键因素.以中国2002—2017年的省级面板数据为研究样本,从理论与实证两个层面分析人口老龄化与碳排放的关系及影响机制.一方面,构建包含碳排放的世代交叠模型(overlapping generations,OLG),发现老龄化主要通过消费效应和生产效应两个路径对碳排放产生影响;另一方面,从实证层面发现老龄化与碳排放之间存在倒"U"形关系,而且消费效应在人口老龄化与碳排放的关系中起到部分中介作用,生产效应的影响则不显著.  相似文献   
3.
以中国2013年以来实行的碳排放交易试点政策作为准自然实验事件,基于2000-2017年中国30个省市的面板数据,运用双重差分法实证检验碳排放交易制度的节能减排效应及影响机制。研究发现,碳排放交易制度有利于实现中国经济“节能”与“减排”的双重目标,并通过了一系列稳健性检验;作用机制检验表明,能源效率提升和能源结构转型都是碳排放交易制度实现节能减排目标的重要路径;能源效率提升在碳排放交易制度实现“节能”和“减排”中分别发挥了10.19%和5.93%的作用,而能源结构转型分别发挥了48.87%和52.95%的作用。这意味着中国碳排放交易制度实现节能减排的主要动力来自能源结构转型,而非能源效率提升。能源结构转型涉及问题更加宏观和深层,这为中国加快推进节能减排进程,特别是完成2030年碳达峰和2060年碳中和的国际承诺提供政策启示。  相似文献   
4.
文章提出“碳化工艺连续化、活化剂复合化、活化技术组合化、活化温度常温化、干燥技术组合化和系统工程化”,应成为我国超细碳酸钙生产技术未来发展的主要方向,并论述了我国目前超细碳酸钙生产技术的现状,用连续鼓泡碳化工艺来改造现有碳化工艺,并提出了超重力反应结晶法的完善办法。  相似文献   
5.
戴火红  徐勤 《基建优化》2005,26(4):112-115
建筑外墙氟碳涂料克服了以往氟碳涂料不能常温固化的缺点,能应用于混凝土等无机材质的表面。由于其具有超耐候性等卓越性能,已受到业主、设计的关注和市场的认可,在外墙饰面中将得到广泛应用。文章浅析了外墙氟碳涂料的材料特性,阐述了外墙氟碳涂料施工阶段的质量事前控制、事中控制和事后控制;对某工程外墙氟碳涂料施工质量缺陷产生的原因进行了分析,提出了相应的预控措施。  相似文献   
6.
基于2013-2020年的30个省份数据构建面板数据模型,从碳排放总量和碳排放强度两个视角研究数字经济发展对区域碳排放的影响。研究发现:数字经济的发展有效地降低了人均碳排放量、碳排放增量与碳排放增速,数字经济与碳排放强度之间存在倒“U”形关系,数字经济与碳排放强度、边际碳排放强度的关系呈现区域性特征,在省域层面数字经济对边际碳排放强度的影响不存在明显的空间效应,数字经济对碳排放增长率的影响存在基于产业结构优化、人口集聚、城镇化的遮掩效应。  相似文献   
7.
The Kyoto Protocol foresees emission trading but does not yet specify verification of (uncertain) emissions. This paper analyses a setting in which parties can meet their emission targets by reducing emissions, by investing in monitoring (reducing uncertainty of emissions) or by (bilaterally) trading permits. We derive the optimality conditions and carry out various numerical simulations. Our applications suggest that including uncertainty could increase compliance costs for the USA, Japan and the European Union. Central Europe and the Former Soviet Union might be able to gain from trading due to higher permit prices. Emissions trading could also lower aggregate uncertainty on emissions.  相似文献   
8.
Through Joint Implementationand the Clean Development Mechanism, reductionsof greenhouse gas emissions achieved abroad canbe credited to domestic firms. However, thetechnical, economic and political risksinvolved may prevent the private sector frominvesting in such projects. This paperdescribes three types of risks which emissionreduction projects are exposed to. Eleven pilotprojects carried out under the ActivitiesImplemented Jointly (AIJ) program and financedby Sweden are evaluated. Actual project costsare found to exceed projected costs in allcases. Annual emission reductions also deviatefrom their expected values and vary stronglyover time, supporting the hypothesis that suchprojects are risky business. The riskmanagement tool portfolio diversification isapplied to a sample of Swedish AIJ projects.The results indicate that diversification canreduce the risks of greenhouse gas mitigationprojects significantly. Thus, carbon funds area promising way of lowering the risks of theKyoto Mechanisms for private sector investors.  相似文献   
9.
Background: Validation of overall survival (OS) extrapolations of immune-checkpoint inhibitors (ICIs) during the National Institute for Health and Care Excellence (NICE) Single Technology Assessment (STA) process is limited due to data still maturing at the time of submission. Inaccurate extrapolation may lead to inappropriate decision-making. The availability of more mature trial data facilitates a retrospective analysis of the plausibility and validity of initial extrapolations. This study compares these extrapolations to subsequently available longer-term data.

Methods: A systematic search of completed NICE appraisals of ICIs from March 2000 to December 2017 was performed. A targeted search was also undertaken to procure published OS data from the pivotal clinical trials for each identified STA made available post-submission to NICE. Initial Kaplan-Meier curves and associated extrapolations from NICE documentation were extracted to compare the accuracy of OS projections versus the most mature data.

Results: The review identified 11 STAs, of which 10 provided OS data upon submission to NICE. The extrapolations undertaken considered parametric or piecewise survival models. Additional data cut-offs provided a mean of 18 months of OS beyond the end of the original data. Initial extrapolations typically under-estimated OS from the most mature data cut-off by 0.4–2.7%, depending on the choice of assessment method and use of the manufacturer- or ERG-preferred extrapolation.

Conclusion: Long-term extrapolation of OS is required for NICE STAs based on initial immature OS data. The results of this study demonstrate that the initial OS extrapolations employed by manufacturers and ERGs generally predicted OS reasonably well when compared to more mature data (when available), although on average they appeared to underestimate OS. This review and validation shows that, while the choice of OS extrapolation is uncertain, the methods adopted are generally aligned with later-published follow-up data and appear appropriate for informing HTA decisions.  相似文献   

10.
国家综合配套改革区与制度的空间演化分析   总被引:5,自引:0,他引:5  
建立国家综合配套改革试验区,不仅是为了促进滨海新区及天津市的发展,更重要的是推动环渤海地区,乃至整个北方地区的发展,形成新的区域发展模式。这就要求在理论上不仅要考虑到技术、制度的因素,也要考虑到空间的因素对国家综合配套改革试验区理论模型的影响。具体研究空间因素对国家综合配套改革试验区的影响有助于准确理解和把握国家综合配套改革试验区的空间作用,形成新的区域增长方式和区域发展模式,为在全国范围内贯彻科学发展观和构建和谐社会提供崭新的思路和视角。  相似文献   
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